CH${}_4\cdot$F${}^{-}$ revisited: Full-dimensional ab initio potential energy surface and variational vibrational states

Abstract

The automated development of a new ab initio full-dimensional potential energy surface (PES) is reported for the CH${}_4\cdot$F${}^{-}$ complex using the ROBOSURFER program package. The new potential provides a near-spectroscopic quality description over a broad configuration range including the methane-ion dissociation, as well as isolated methane vibrations. In particular, it improves upon the earlier [Czakó, Braams, Bowman (2008)] PES over intermediate methane-fluoride distances. Full-dimensional (12D) variational vibrational computations using the new PES and the GENIUSH-Smolyak algorithm show that tunneling splittings larger than 0.1 cm${}^{-1}$ appear below the top of the interconversion barrier of the four equivalent minima of the complex.

References in corpus (3)

• Towards breaking the curse of dimensionality in (ro)vibrational computations of molecular systems with multiple large-amplitude motions
• Variational vibrational states of HCOOH
• Fingerprint region of the formic acid dimer: variational vibrational computations in curvilinear coordinates

Cited by in corpus (3)

• Exact quantum dynamics developments for floppy molecular systems and complexes
• Variational Vibrational States of Methanol (12D)
• Exact quantum dynamics of methanol: full-dimensional ab initio potential energy surface of spectroscopic quality and variational vibrational states